how to upgrade 2009 27 ' mac?

CRS6283 wrote:

how can I upgrade my apple 27'' it works well but google says they dont support my OS anymore?

A Late 2009 iMac can be upgraded to High Sierra 10.13.6. To upgrade any further you wold need a newer Mac.

Hi,

You can upgrade till Snow Leopard which is available at eBay or similar services.

I'm not sure it's still at retail/online AppleStore, though.